XI International Meeting on Paracoccidioidomycosis

XI International Meeting on Paracoccidioidomycosis

Resume:112-2

Poster (Painel)

112-2

Sporothrix mexicana as the etiological agent of human sporotrichosis

Authors:

Anderson Messias Rodrigues (UNIFESP - Federal University of São Paulo) ; Geisa Ferreira Fernandes (UNIFESP - Federal University of São Paulo) ; Priscila Oliveira dos Santos (UNIFESP - Federal University of São Paulo) ; Cristiane Candida do Amaral (UNIFESP - Federal University of São Paulo) ; Alexandre Augusto Sasaki (UNIFESP - Federal University of São Paulo) ; Zoilo Pires de Camargo (UNIFESP - Federal University of São Paulo)

Abstract

Sporotrichosis is a reemerging disease that affects humans and animals. The disease is characterized by lesions in the cutaneous and subcutaneous tissues. Classically, the disease is known to be caused by Sporothrix schenckii, an anamorphic ascomycete of the order Ophiostomatales. Between 2004 and 2010, 151 isolates of S. schenckii were obtained from different regions of Brazil. Phenotypic characterization, such as the growth at various temperatures for colony diameters measurements, macro and microscopic features, and carbohydrate assimilation (dextrose, sucrose, raffinose, and ribitol) tests were performed. Using the key features for Sporothrix species and the partial calmodulin gene sequence, we identified three isolates of S. mexicana. All three Brazilian S. mexicana isolates showed a 100% match with the CAL sequence of S. mexicana (CBS 120341) in BLAST searches. The three isolates of S. mexicana identified in our study were obtained from human cases of sporotrichosis; the first case was obtained from a patient in the southern region of Brazil and the other two cases were obtained from patients with sporotrichosis who lived in the northeast region. One isolate of S. mexicana showed an atypical carbohydrate assimilation profile (raffinose was not assimilated) while the other two isolates, as well as the two reference strains of S. mexicana assimilated raffinose. The macroscopic morphology characteristics of the three Brazilian S. mexicana isolates, as well as the S. mexicana reference strains CBS 120341 and CBS 120342 were very similar. Recently it was demonstrated in literature that S. schenckii is not a single specie but a complex of phylogenetically related species, including S. mexicana, S. globosa, S. brasiliensis, S. luriei, and S. schenckii. Since then, only three environmental strains of S. mexicana have been found in Mexico and Australia. The three Brazilian S. mexicana isolates included in our study had been maintained in fungal collections since 1955, indicating that this species has been present in Brazil for a long time. To the best of our knowledge, this is the first report about the isolation of S. mexicana from human clinical samples. Our study provides new insights into the epidemiology of sporotrichosis.਀ This study was supported by FAPESP, CNPq and CAPES

Keyword: Sporothrix, Sporothrix mexicana, Sporotrichosis, Brazil, Taxonomy

਀�